The Covid variant named XBB1.5 has more contagion capacity than the Omicron from which it arose. It spreads through different regions of the United States and became the main source of infections, which are on the rise.
The Centers for Disease Control (CDC) reported that the XBB and XBB1.5 subvariants already accounted for 44.1% of all infections in the last week of 2022. A week earlier, the CDC had these subvariants with 25 9% of the cases. In the week of December 15 it was barely 10%.
“Our concern is how contagious it is,” World Health Organization (WHO) epidemiologist Maria Van Kerkhove said from Geneva. “It is the most transmissible subvariant that has been detected so far,” she added.
XBB1.5 has already been detected in 29 countries worldwide.
At the moment there is no data indicating that it is more deadly or causes more serious infections. However, “the more this virus circulates, the more opportunities it will have to mutate,” says the WHO epidemiologist.
This adds to existing concerns about more infections in China, which has just opened its borders after almost three years of strict restrictions.
These variants, according to the infectologist, have the ability to “adhere to human cells more easily and replicate quickly.”
In the United States, the average number of hospitalizations in the last week stood at 470,699, while in November they were below 300,000.
The new mutation was first detected in October 2022 in New York and Connecticut. In New York, these subvariants mean 75% of the cases. In Connecticut they amount to 86.2%.
Experts say that existing treatments seem to maintain their efficacy against the new subvariants.
A year ago, a strong escalation of the Omicron variant spread across the Earth. Around 25 million daily positive cases were registered, seven times more than today. The difference is that now there is a lower level of testing and a higher level of vaccination.
However, in New York, hospitalizations grew. According to its Department of Health, the current rate is 22.26 per 100,000 residents, the highest since February 2022. The data does not discriminate between Covid and respiratory diseases, typical of cold winters.
“We expect new waves of infection in the world, but that does not have to translate into new waves of death, because our measures against the virus continue to work,” Van Kerkhove stressed at a press conference.
In the United States, the CDC warns the population about the importance of receiving booster doses.
In that country, which registered the highest number of deaths from covid, 70% of people received two doses, while 15.4% of those over the age of five had more than two doses. This is a low ratio. Among those over 65, considered the population at greatest risk, the proportion reaches 38.1%.
Washington this week requires a certificate of vaccination for foreign visitors to the United States. Travelers from China must also submit a test no more than 48 hours prior to the flight.